Sickle cell disease is a common B hemoglobinopathy which results in substantial morbidity and mortality. SCD is characterized by a procoagulant state which likely results from the interaction of sickled red blood cells (SRBC) with the endothelium. Hemostatic abnormalities in SCD include an increase in procoagulant factors via an increase in tissue factor (TF) production as well as a decrease in anticoagulant factors in the protein C pathway. The result of this imbalance is a well characterized increase in thrombin formation. Low molecular weight heparin (LMWH) is a simple, effective and safe means of anticoagulant therapy which could be used to treat SCD manifestations but has never been evaluated in sickle cell disease (SCD).